T(d) is a function that relates the number of tickets sold for a movie to the number of days since the movie was released. The average rate of change in T(d) for the interval d = 4 and d = 10 is 0. Which statement must be true?
A: Fewer tickets were sold on the fourth day than on the tenth day.
B:No tickets were sold on the fourth day and tenth day.
C: The same number of tickets was sold on the fourth day and tenth day.
D: More tickets were sold on the fourth day than on the tenth day.